I actually don't have one unless it is open.
I can sit and ignore a box of chocolates if it is still sealed.
I could sit and ignore a jar of nutella (can't have it anymore due to dairy allergy) if it had not been opened at all.
I can sit and ignore raspberries if the container is still sealed (don't ask about them on the bush).
I can ignore strawberries, blueberries, crowberries, cloudberries, and so on, if they have not been opened. Again don't ask about them growing wild or in my garden...
I can ignore a box of biscuits....
I can ignore sweets....
I can even ignore a jar of treacle if it has its seal...
And the same applies to garden peas. But I've been known to eat them frozen. If they grow in the garden, they rarely if ever make it inside the house...
I have no discipline once something is open. So generally I don't buy it!